Distribution and Antimicrobial Resistance of Non-Tuberculous Mycobacteria during 2015∼2020: A Single-Center Study in Incheon, South Korea

Abstract

This study sought to investigate the distribution, antimicrobial resistance rate, and bacterial co-infection frequency of non-tuberculous mycobacteria (NTM) in a single center in Incheon, South Korea. A total of 8,258 specimens submitted for tuberculosis (TB)/NTM real-time PCR tests during the years 2015 to 2020 were retrospectively reviewed. In total, 296 specimens (3.6%) were NTM positive, and the positivity increased from 2.5% (30/1,209) in 2015 to 3.8% (66/1,740) in 2020. Of 296 NTM specimens, 54.7% (162/296) were identified as the Mycobacterium avium complex (MAC) followed by the Mycobacterium abscessus complex (MABC) 20.9% (62/296), M. fortuitum 6.4% (19/296) and M. flavescens 3.4% (10/296). Of the NTM-positive specimens, 76.7% (227/296) were tested for drug resistance. The results showed multidrug-resistant NTM in 40.1% (91/227) and extensively drug-resistant NTM in 59.9% (136/227) of these specimens. Of the 145 isolates taken for bacterial culture, bacteria/fungi co-infection with NTM accounted for 43.4% (63/145), in which the most common bacterial species was Klebsiella pneumonia (23.8%, 15/63). This study is the first report on the distribution and antimicrobial resistance of NTM in Incheon. As the proportion of NTM infections increases, active treatment and thorough infection control are required for effective management.

Keywords

• co-infection
• drug-resistant
• incheon
• non-tuberculous mycobacteria